Acquisitions Of Businesses (Details) (USD $)	0 Months Ended		1 Months Ended	3 Months Ended
	Dec. 02, 2013 Company	Jul. 29, 2013 Company	May 31, 2013 Company	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Business Acquisition [Line Items]
Business acquisition date	Dec. 02, 2013		May 31, 2013
Goodwill				$ 834,102,000		$ 834,825,000
Number of businesses acquired	1	1	1
Non-cash income from contingent consideration arrangements				0	500,000
RepconStrickland [Member]
Business Acquisition [Line Items]
Business acquisition date		Jul. 29, 2013
Business acquisition, percentage of voting interests acquired		100.00%
Purchase price		463,600,000
Proceeds from revolving credit facility		250,000,000
Working capital acquired		35,500,000
Other net liabilities acquired		67,100,000
Goodwill		267,800,000
Identifiable intangible assets		227,400,000
Acquired goodwill, tax deductible amount		$ 49,000,000